Heat exchangers of the type utilized in vehicle engines may be used for cooling engine coolant or refrigerant vapor, or other engine fluids. Parallel header and tank units are included with parallel tube passes extending therebetween, and air centers connected between the tube passes for directing the inlet air stream. The heat exchanger is located near the front of the vehicle for receiving air flow as the vehicle is driven in a forward direction. The engine fan tends to draw cooling air across the condenser while the vehicle is stopped or slow moving and the engine is idling.
Aluminum tanks utilized in heat exchanger apparatuses have included a separator or end piece which is to fit within the aperture formed by the walls of the tank. Internal sides of the tank generally offer only line-contact with the separator part. The interface of the separator, aluminum header and tank along the surface where alloy will flow during brazing is extremely critical to part fit-up to prevent voids. The separator edges interconnect with the tank and header at an interface which is braze sealed. If the components are misfit the braze seal may leak. In condensers, performance may decrease if Freon leaks occur internally at the separator or if Freon leaks occur externally at the separator end cap. Likewise engine cooling is adversely affected by coolant leaks. Manufacture of the parts to close sealing tolerances is critical and difficult.
One such system is disclosed in the U.S. Pat. No. 5,009,262, issued Apr. 23, 1991 in the name of Halstead et al. and assigned to the assignee of the subject invention. The patent discloses a combination radiator and condenser apparatus having extruded tank and header units with a partition therebetween for isolating the coolant and refrigerant. The extruded tanks generally comprise a longitudinal cylindrical member having end closures seated therein. The side walls of the extruded tanks have cold extruded channels formed therein to receive the side walls of the end closures when they are inserted through an access slot of the header. The mounting rail is also cold extruded to form a pocket or channel for capturing the end of the end closure. However, there the partitions are not configured to produce a repetitive precision fit which will assure a positive braze seal between the tank, the partition and the header.